The use of electro-magnetic fields for treatment of cancer by causing lysis to cells that harbor, or are in close proximity to particles responsive to such fields, is known. The techniques involve using a micro sized particle, typically below 0.1 μm, which for example comprises an iron oxide core and is coated with a polymer. Typically a secondary coating is applied where the particle is activated by chemicals that show specificity for biological targets of interest. The aim was to concentrate particles at the site of a biological target, where a specific chosen target can be an exclusive marker, expressed for example by cancer cells, and presented on the extracellular side of the cell. Target cells are then destroyed thermally by means of absorption of energy from the electromagnetic field.
Efforts are being made to improve techniques by focusing on factors, such as clearance of particles from blood before reaching the target cells; binding unselectively to other than target cells; toxicity of the particles in use and insufficient effect from induced electric fields to cause killing of the target cells.